11_初始化剩下的单实例bean

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// Instantiate all remaining (non-lazy-init) singletons. 初始化剩下的单实例bean finishBeanFactoryInitialization(beanFactory);

1. 初始化容器中的类转换器，id 为conversionService

   // Initialize conversion service for this context.
   if (beanFactory.containsBean(CONVERSION_SERVICE_BEAN_NAME) &&
       beanFactory.isTypeMatch(CONVERSION_SERVICE_BEAN_NAME,  ConversionService.class)) {
       beanFactory.setConversionService(
       beanFactory.getBean(CONVERSION_SERVICE_BEAN_NAME, ConversionService.class));
   }
   

2. 注册值解析器

   // Register a default embedded value resolver if no bean post-processor
   // (such as a PropertyPlaceholderConfigurer bean) registered any before:
   // at this point, primarily for resolution in annotation attribute values.
   if (!beanFactory.hasEmbeddedValueResolver()) {
       beanFactory.addEmbeddedValueResolver(new StringValueResolver() {
           @Override
           public String resolveStringValue(String strVal) {
               return getEnvironment().resolvePlaceholders(strVal);
           }
       });
   }
   

3. AspectJ相关

   // Initialize LoadTimeWeaverAware beans early to allow for registering their transformers early.
   String[] weaverAwareNames = beanFactory.getBeanNamesForType(LoadTimeWeaverAware.class, false, false);
   for (String weaverAwareName : weaverAwareNames) {
       getBean(weaverAwareName);
   }
   

4. 对beanFactory做一些配置

   // Stop using the temporary ClassLoader for type matching.
   // 停止使用临时的ClassLoader进行类型匹配。
   beanFactory.setTempClassLoader(null);
   
   // Allow for caching all bean definition metadata, not expecting further changes.
   //允许缓存所有bean定义信息
   beanFactory.freezeConfiguration();
   

5. 初始化剩余的单实例bean

   // Instantiate all remaining (non-lazy-init) singletons.
   beanFactory.preInstantiateSingletons();
   

   1. 获得所有的bean name

      List<String> beanNames = new ArrayList<String>(this.beanDefinitionNames);
      

   2. 循环遍历beanNames
      • 获取bean定义

      RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);
      

      • 初始化的bean必须满足的条件 - 非抽象类&&是单实例的&&非懒加载
      • bean如果实现了FactoryBean，则使用FactoryBean的getBean创建bean；否则使用getBean创建bean

      for (String beanName : beanNames) {
          RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);
          if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) {
              if (isFactoryBean(beanName)) {
                  final FactoryBean<?> factory = (FactoryBean<?>) getBean(FACTORY_BEAN_PREFIX + beanName);
                  boolean isEagerInit;
                  if (System.getSecurityManager() != null && factory instanceof SmartFactoryBean) {
                      isEagerInit = AccessController.doPrivileged(new PrivilegedAction<Boolean>() {
                          @Override
                          public Boolean run() {
                              return ((SmartFactoryBean<?>) factory).isEagerInit();
                          }
                      }, getAccessControlContext());
                  }
                  else {
                      isEagerInit = (factory instanceof SmartFactoryBean &&
                              ((SmartFactoryBean<?>) factory).isEagerInit());
                  }
                  if (isEagerInit) {
                      getBean(beanName);
                  }
              }
              else {
                  getBean(beanName);
              }
          }
      }
      

      注：getBean创建bean的过程
   3. 再次循环遍历，如果实现了SmartInitializingSingleton接口，则回调afterSingletonsInstantiated